Method for producing white sodium rosinates



Patented Aug. 20, 1946 METHOD; onrnontromawmm: sonwmnosnmms AveryrAi Morton, Watertown; Mass:

7 NoDl-awin'g. Application January 21,, 1942,

' Serial'No.'427;679"-. I

. 1, t This "invention relates to's odium'ro sinates an d method for producingithe same;

More'sparticularly it relates :to :the producing and isolating-of alkali meta-l:rosinateswhichihave the-:peculiar :characteristicsthat they are white; and also thatitthey are': free from certain objectionablelifeatures hitherto considered' :typicalof rosinates; I The invention: issherein i'll'listrativ'e'lydescribed:

with reference to its bearing ionlthe soap indus- 10'' try; because of: its promoting:rosin :to-thestatus of ihaving-amarket and cooperative utili'ty among; materiallyfor makingfii'st classsoap: The high value 'ofi'the rosin'ate of the:invention-*in this respect comes iirom the fact that it enables white soap to have the advantages which u atten'd the useof "rosin; and yet 'befree from defects an'd disabilities, hitherto 1 considered 1 inseparable, which: have excl'uded rosin Irom s'oap of: that class." But the: utility is not limited'f -to: soap:

Many orall industries using rosinates or I rosi-n may' benefit; and" with the aid oF-this -invention' the introduction of -rosin products into -still 'other field' vmay b'e expected;

- Hitherto rosinchas depreciated soap b'y impart mg to it a disapproved characteristic yellowish brown color. Bars of white soap em body ing thewhite .rosinate of th'e: invention have been found not 'losing I their whiteness as=they age undr or overzlrosin asheretoiforeusedi I have demonstrated: that" from the gsodi'um'= rosinate of: ordinaryuse there 'canb'e pro'dueed And there are improvements ln oth'er respects twodistinguishable substancesaboth of which are 3 rosinates. As hitherto knowmthese are so thor oughlyintei'mingrled; aresso: much alike-and; in mixture, are so dominated by 'tlle characten of: one of them that the benefits ofithe other of them have not 'before been availableon even-- known; 401

so fa r as I 1 am 1 aware: Whatever "the chemical distinction that mayultimately be found between"- these 'two,'- the present-' specification -disclosesa; way of producirigrthem separately from the customary -"ro'sinatea" It' -issufficiently distinctive:-

for purposes he-r-eot -to --desig-nate these respectively dark resinateand white rosinatefi My: discovery of the-whitrosinate;and iof a way to segregate-it; contributes-to industry rosinates"ofs :Glaiinsa (01. 2605-) trially useful for all purposes for which the customary rosinates heretofore known can bet ap plied, lacking no-useful function by area'son ofi the absence ofa the dark rosinategbut being-xfree from the burdens --h'itherto attending :rosinates." The process of segregation includes a step which utl lizes the preferential afliriity oi a rosin :solutim's for the 1 dark rosinate. The dark rosinate, and re'senes and esters; can-be separately recovereds for uses to which they 'are appropriatei The closest approaches of prior art, known to me, arefound among methodsiproposed 'for lightening thecolor of rosin or rosi-natessbut noneof those; nor any of those wh'ich separate the resin; intq'flcomponents or crystallize it as abletic acid; has resulted in furnishing white =rosinate='for thesoap maker. This" is so =universal lyrecognized that theexpression rosin soap and yellow soap are practicallysynonomous.

Among these prior proposals,- that shown in United States PatentsNos; 2,0855151 -and 2', 085;152 issued to Georgi wouldtreat a solution 'of abi'etic acid or resin; preferably a ten per cent-solution; in a solvent which is a non-solvent ot'the alk ali and of the abietate, with alkali sufllcient to substantially; neutralize the-- abi'etic acid present?" The 'product 1 of thistreat-ment is' -stated to-be= alkali abietate in rather purg-form;-. that i'sg free fromresenes'-or'the likef and thesepatents also say their product is substantially tree- I-r omcolor bodies"; but tests' show that color bodies are-- present in appreciable quantity. The patent to Kesler---No-. 1,633,? 64 proposed to precipitate the alkali acid salt-while anew-mg the 'resenes co -re 1 main in solution -to make a-"product which d'oes not become moist and sticky, and from which 'is= obtainable abietic acid free of impurities?" Howev'enit removesonlythe -resenes andwhat--- ever of the-color:bodies'are:present-in the resenesr The product stillcontains =the-colored-' saltset" rosinacids. Inthe; process of Frencl-1'--- 'N'er 2,01'2;1-25 for highly purifying rosin; an aqueous petroleum suspension of rosinat'e is del iyclrated byhot petroleum'sothat*thealkalrresinate'separates-from theso'lution. The crystals-cr menew product are, according to the patent; readily amenable to washing or otherzpuriflcation treat=- men Th'e product-obviously was :not whiten None of. these method's for =improving the color sod-hint (another alkali that appear to be indus- 50'? make a rosinate usable in white soaps Mere're- V t ledesired saturation,-

' i ;'I-o1demonstrate-the invention one may obserye that dry sodium ,moval of the resenes and such color bodies as are part of the resenes, i. e. unsaponifiable matter, is

{not suflicient. a I The inherent inability of prior procedures to separate whiterosinates from dark is perhaps the reason why white rosinate has, so far as I amaware, remained unknown until my discovery.

The discovery has shown further that the obl jectionable features'of rosin in soap are not associated with all rosinates, but are more particularly attributes of the substances which the invention eliminates. I show that there is a difierence of solubility, as well as of color, between the dark and the light; and further that all of the substances having offensive color characteristics,

:normally found in the mix after treating rosin .taining a quantity of dark sodium rosinate, can be added to 190 cc.,of kerosene, and the mixture with a base, can be held, preferentially overthe ,white rosinates, in a solution herein' described.

The described procedure is successful without needing an exact theory as to how or. why this is so.

To understand my attainment a product inate is present than can be dissolved withthe given amount of rosin, the dark rosinate will be taken and held preferentially, leaving more or less of White'rosinates in a solid form which can be recovered by filtration. As an illustration of this theory, g. of a powdered dry sodium rosinate, made from WG rosin and therefore conheated to 140 C. with stirring, without there being any appreciable dissolving of the rosinate. However, upon adding 40 g. of rosin, and repeating thefprocess of heatingand stirring over a period of-two hours, most of the rosinate becomes dissolved. When the whole process is repeated using 80 g. instead of 40 g. of driedso- V dium rosinate a large portion of the rosinate re- -mains undissolved. When recovered by filtration fthis material is found to be white.

having the whiteness which is demanded'in"soaps of high quality one maybear in mind the fact 3 condition for operation of the process.

The process comprises a treating of rosin with a base, and 1a separating of, the product into two parts; ,one ofwhiehgha the white sodium rosin-j ates.;:,- 1The:other parl11is a solution containing all ,of-theicolored substances, including darksodium rosinates, resene's, rosin esters, andsome unneu-.

tralized rosin. This solution is amenable to further separation if .desired. The preferential solbi ity ofthe dark substances depends upon the solution holding also a suihcient-concentration of rosin. Thegreater the concentration of-rosin in the solution, the more surely will the dark rosinfates beheld in solution, p V i. For greatest economic efficiency, the quantity of solvent and the concentration of rosintherein mustbe selectedor adjusted. so thatthe rosin-- ate dissolvingcapacity, made by the concentradarkrosinates, in addition to the resenes, esters and other colored components; and yet is limit- ;ed so that the solution will become saturated when should be prevailing at the'stage whe n the white a ratio of alkali makes moreflsodium rosinate, than I the solution can hold; thefraction that precipi-v Another-.method for demonstrating the theory which underlies this invention is to add a limited quantity of sodium carbonate to a petroleum H solution of rosin. As the carbonate reacts with therosin' and forms sodium rosinate, the latter goes into solution. Theaddition and reaction of more and more carbonate eventually produces more rosinate than the solutionican hold. The white sodium rosinate then comes out of solution as a precipitate and the dark colored rosinate, is held preferentially. By adjusting empirically the quantities of alkali,; rosinand'hydrocarbon solvent-it is possiblev to produce a highly desirable As a specific illustration of this second; method of showing the solubility. of sodium rosinate-in a p'etro-g leum solution containing rosin,.and also as a demonstration 91 10118 method of practicing this inventiomthree case are herejgiven: First, (a) usejofalkali in what may, for this purpose, be called a flow? ratio (of, alkali make sodium rosinate that will remainin solution, gbecauseof the solubility of allysodiumrosinates in a solvent 7 which-also. iholds .unneutralized rosin in solution. Itis assumed in each'of these, illustrations that the-process. is run a long as the sodium rosinate continues to be formed at a reasonable rate. Second, (1)) whatmay be calledv a,moderate tates out is a white rosinate;. and whatever dark rosinate. is, present continuesin solution But (0) with a ratio of alkali so. 1large that most 1 .of the rosin acid becomes neutralized,,,the power t on of rosin,.i suflicient to take up all of the v Zall of those have been taken up, so that no conrosinates are beingseparatedfronrthe solution:

Before that stage the concentration of rosin pres-- ent, will preferably be great enough so that it can undergo diminution with the progress of the reaction; and-yet becorrect inamount to produce ature of iiltration.

theory which underlies this rosinate isinsoluble in kerosene. If, however,

at the time and temper-;

of the white anddark sodium rosinate, and there-- fore is not white. Thusgby,selecting-the'propor tion of alkali which is introduced fOrthe reaction, whiteness of precipitate "can. be obtained, care being taken-that the concentrationof rosin.-

does'not become too much reduced.

. Quantitative examples illustrative. of the goingcasesfollowu r (a) The addition at sene to make a total volume of approximately 1750 cc., which makes the concentration of rosin *be about 36% in the-tqtalweight of solution, if

the kerosene has a specific gravity of 0.73, causes the described reaction,;which can proceed. to a;

conclusion in about one and one-half hOurs with-' out the temperature-having risen ;ab ove-133 C However, the sodium saltwhichjias; been pro,-

ducedremains largely dissolved l -the reaction,

fore-I 10., with stirring, of

40 g; of anhydrous sodiumcarbonate to 'asolutionf *of 480g; of WG rosin,jdissolved in enough keromixture,- even" when the kerosene solution isallowedtocooltoroomtemperature: -Irr-case-'(b'); where the -ratioof carbonate 'to rosin isy say 2 to --l2 instead of 1- to' l2j' and the heatingandwtirring is'-carried--out until 'reaetionfhas been-effected'at a; final temperature of 145 Ci; a precipitate *is produced-which white or sonear to -white that; after separation" from the solution and fr'omadhering liquidg it' is suitable for use in "whitesoap; or for use as a'high quality of sizefor paper-,"or-ror any use for which afwhitesodium rosinate may bedesi-red;

But when the* ratio of carbonate "to'rosin is made 3 te -12the colorof the precipitate-has been found'to fall into--the-range of-"grayishwhite or tan; If a still 'higher proportion ofalkali is used the "color becomes brown;

The foregoing'examples respectively show; first;

all "sodium 'rosinates caused to dissolve in a"-hy"- drocarbon solvent by-the-presence of-rosin; second, dark rosinate--kept in the solution -prefer= entially, while the-precipitate i entirely white rosinate; and; third-, dark rosinate precipitated to some extent when therecomes *to :be-'-st-illless rosinpresent in the-solution These also show that practice 'of this invention may require adjustment of a numberot factors;-

. The I principal :variables in the =proces are', (A) concentration'of rosin in the-solverit; which is best kept-as high as =possible, for 'it' diminis'hes continuously throughout a reaction in which rose mate is being produced, and yet sh'ould' at; the enclof reaction besuch that the colored rosinate andall other color-ing matter is: surely held in solution in the motheri'liquor; (B) adjustmentof the ratioof: alkali present for the reaction-1(0) selective control of the temperature; which'must be 'high' enough to effect reaction; and attimes high enough to. increase the-solubility so as to prevent precipitation of :dark rosinate, but' preferably will'be 'held to moderate limit-s, in order that cracking oi the rosin-acids shall be avoided; (D) suitable:agitatiom-themore vigorousithe better, to -make good contact between thesolid'alhali and i the rosin acids, and' .to promote prompt es i cape oral1- volatile products; (E) adjustment as to the duration timeysince sthe ros'inateafirst'pre: cipitatedwill be whitepbut flahat precipitated later may be dark as when thepr'ocessgoesztocompletion; and the ireduction" of 1 concentrations of the rosin in th solutiom. andithe icurrentl conditions as to quantityvof 'alkali temperature:onother factor may be; or mayaco'me to be; suchithat toward the .end darkx'bodi'esi ares precipitated; .(F)' rprefer ably; that the source material ichosen should the cleaned crude gum, or elsefb'e :lightvcoloredmosirr; and (G) for the best commercial success, that the solvent and the alkali be of inexpensive kinds,

for which at present'kerosene and'sodium'car bonate are satisfactory.

Theinvention can be practiced with wide variation of these conditions. given observations pertaining when there is a relatively high concentration of rosin, which mighti'be called a preterredi=region for operating the process. In this the above mentioned variables can be ichangediwithin wide limits without greatlyaffecting the result. Second, thecasewill Herein will first it should b e understood that =the pre-determirla tion of the adjustment of-factors to housed in any practicing or the process industrially can {if necessary f always-' be -approached empirically by allowing sodiiim carbonate' or other suitable alkali to react with rosin, in a- 'solvent' having s; high concentration of rosinyand the' progress on-reaction with precipitation ofsodium rosinate be ob served until= the obtainable --quanti tyof white sodium rosinate hasbeen formed; and? adjust ments made of rosin concentration, alkali, ternperature; and duration as-may bedesired.

The proportion of" rosin -inthe solventis the most important of the factors-mentioned -above-, for if i the initial -concentrationof rosinis *suifi c'iently hig'h the concentration existing at the end ot the reaction will not have 'fallenso low as to fail to holdin solution the-undesired-rosinateand the other undesired substances Although-'- the having of th'e concentration "adequate=at the*-time of separation ofthe white rosinate is of ultimate importance;=- it is' m0St practical and informato-ry to state the concentrationof: rosin- -in-=- terms of the: amount at the A beginni'ngaofreaction; ae is done inthe-eXam-ples here given; 1

However, in any instance the concentration of rosin existing atthe tir'ne of *fi'ltration carr be found (by 7 analysis; Concentrations so -found-ein aseri'es of trial-operations on-samples can be used as a guide to select" the initial concentration to be employed in a main operation on -any partic'u' lar lotcof I'OSil'li- In vari'ous lotsthe contents of dark r0sinate:-may--difier; J Iff it is-desired toaattain the i highest practicableayield oi wl'i'iiie r1 rosina-te; with a minimum of attendant costs, the concern tration of resin for dealing with' any p'articular lot should -suoh as Will ';-makethesaturation point for rosinatessoccur whenall of the da-rk rosinate has been dissolved, and approximately all of the whiterosinate remains' undissolveds By a series ot laborator-y tests applying the process to samplesx from a particular-lot with diminishing concentrationsof rosin, in successive samples until ;one;is ifound "whose isolated rosinate product is not-white: it can' be learned which initiat 'ros-in which has passed through the filter, with water to take out isodium rosinate equivalent to what was in solution at the time of filtering; then extracting-the rosinthereof'with sodium carbonate; and after that distilling away the mother liquor to recoverresenes and esters. 'I'hisseriesciopen anions-(provides dataaby, which concentration of combined and I uncombined rosin .i acids andor 1 other constituents may: be: calculated: "TlIB'QllQII-i tity of solvent... may be: assumed notito have changed appreciablyduring the reaction; but if I any. is known to have been lost or addedfidue allowance canbe made; Thewei'ght of combined rosin is'obtainablepbyacid treatment offthe rose inatesfound in'theresidue and those foundfin the filtrate. Thetotal of combined andjunconi bined rosin, plus the smalleamou'nt of resenesand esters; found by this analysis, i comparable with tion of rosin required to be provided in therosim solution, for-the filtration step, in producing white rosinatefrom the particular-lot of'i osin thus sampled, canthu's be known. I I

. The. best form of the process in brief, involves 1 the making of anon aqueous mixtureof alkali; withaninert'solvent holding in solution a very high concentration of rosin acids,- although'not too high for agitation to be effected, about 45 to 50% by weight if petroleum with a specific gravity of. 0.73 is used heating,stirring and maintain- I ing fluidity in the thick mixture while reaction producingrosinate continues at restricted temtain in solution all rosinates and other substances having color; separating thejprecipitate from the 1 solution by filtration; and, if desired, washing the i separated matter clean of themotherliquor, to j make the final product, Details will appear hereinafterof steps andrestrictions that may be i applied for controlling the source material, the

solution and the fiuidityofthe mixture, the reac- 16 perature fractioning the soluteby precipitating 1 the. white rosinate from solution while themother j liquor has sufficient concentration of-rosin to re- 8 particularly if the mass starts to gel. The petroleum may advantageously contain some low boiling fraction, which byits own volatilization will facilitate the removal of the small amount of water' that is formed by the neutralization of the rosin. Removal of this small amount of water helps to prevent gelling. A little additional pe troleum may be added to compensate for any loss by volatilization, or to facilitate the stirring if the mixture becomes extremely thick. Stirring is continued while the mixtureis held at 140= C. to 150? C. during the last hour, without the temperature rising materiallyabove the limit indicated, until the reaction is substantially complete,

shown by cessation of escape of water or of carbon dioxide set free by the-reaction. The mixture isthen allowed to cool to about 120? 0., where it is filtered to separate the precipitate, more of which comes out of solution as the mixture cools.

7 tion, and the fractioning of the solute. These may f vary,;considerably, relative to each other, while i still-givingran optimumof whiteness. Also they may vary among themselves according to the grade of final product which is wanted, in case 1 it is adjudged admissiblethat the extremely white 1 be slightly shaded by containing a. modicum of 1 lower grade mixedwith it, for lower cost or greater yie1 1 I 1 Thetermfr'osin as used herein may be conare illustrative examples in which,

50%. -A;result of this high concentration is that rosinate-is precipitated., Formation of sodium Q sidered to include any material'whose acid come ponent has the composition of approximately T CzoHsoOz. j In TableI 1 at the beginning, rosin was concentrated in kero- 1 I 1 sene in the high ratioof about 1 g. of rosin to 1.1 3 g. of petroleumsolvent, a concentration. of about 3 rosinate and evolution-f... carbon dioxide and water. begin at a temperature onlya little above I,

100.? Ci,faccording to the equation:

Filtration can be carriedout at or even lower but the mixture is correspondingly thicker and harder to filter. The precipitate is found to be snow white sodium rosinate. All color bodies, particularly the dark colored sodium rosinates, pass through the filter because the rosin is still sufficiently concentrated to hold them in solution in the mother liquor, in which the white sodium rosinate is relatively insoluble, so that it is retained by the -filter. The filtration can be effected by any of the'recognized varieties of apparatus, including the centrifuge.

, The centrifuge will ordinarily leave the precipitate'suificiently clear of the mother liquor, but, if

desired, the whiteprecipitate maybe washed with 7 small quantities of kerosene or other petroleum,

to remove the mother liquor from it, untilthe liq uid coming away is colorless; Low boiling petrO:

leum can be employed to remove higher boiling wash liquid; and the low boiling petroleumf can be cleared away by promoting, its evaporation.

If itis desired to, separate the unreacted excess of alkali, that was'retained by the filter with, the

rosinate, this canbe cleared from the rosinate by dissolving them both inwater, and then salting out the rosinate, or in any other known manner.

If the White rosinate is to be used in soap thisstep 7 can be postponed and the result attained at'the corresponding stage of the soap making.

The completing of filtration is considered to end the process of theinvention, the white rosin'-.'

atebeing then isolatedfromthe dark rosinates. The free alkali-thatimay be present with it is in-Vv consequential; This would be some of the alkali that was introduced for the reaction but became H cob eN 'z ow I V covered by precipitated rosinate and thereby was.

:- 7 v 2C19I;I2 9COONa+COz+HzO prevented from reacting.

I .TABLEI I l i Q V Concentra- V l Percent a 7 So]. tion ofrosm 'Max. No. B02111! :IGrade g vol., to 531 insolution, temp., Time 2 3% 7 Color V J u e cc. .vpement ,percveutby' O. ,P

39, 285 v 32.5) 49 150 2.5 so sn jw white. .31. Mesa 25.9 49 150 2.5 so Do. .48 280' 40: 50 150 -25 s1 Do. -31 285 25.9 49 .150 1.5 13v Do. 35 285 152 1.3 70. Do.

"Anhydrous sodium carbonate having been intro- ,duced into the solution of rosin in kerosene at or 1 below C., heatingis continued so that .in an hour thetemperaturehas risen .to about 14030.

lThe mixture usually'becomes ver 'thick,and 1 stirring miust be f vigorousfjto maintain fluidity,

In Example 5 the rosin was first dissolved in 800 cc. of ligroin, filtered while cold, concentrated-,;

:93? exaclzwpercentagesaare?inot -knowng in thisuexample because thecquantity' ofipetroleum-insoluble material, which was separated before-carrying out the process,..reduced the a ctual. weight g'of rosin used. z

10 careraatothe ratio of alkali to: rosin, themaking oi adj-ustment of the ratio of alkalimeans that theuantity of :alkal-i'whichwill give the desired result should be determined-empirically, and that the. quantity used, in proportion .to sthe other --,'Simi1ar= operations usine'zwas sourcev material 5 substances present, be limited accordingly. The crudepgum -of; a.1.kind whicha-would ordinarily secondg-rex-ampleabove -giventgof the --th,eor y;:unproduce WG rosin; give; parallel: results,; as shown .derlying. the; process. shows how; the. quantity i .of in.'.l?able;1I.v v I l n alkali can be adjusted empiricallyvso. thatm Pmd f 5 Theta-II L "Percent Rosinin v I No Gum, NazOOg, alkali esolutionr :tTlme, jrYien. Color I, -g. I .--to'rosi n,.1: pencent by C .,.hrs., .perzcent I ,percent,. weight 6 156 31 285 26 49 146 s30; Snow white. 7 152 39 285 33 50 150 I 2.5 I so Do. I

As the crude gum source material waslaboutv not of suitablewhi'teness is'ob'tain'ed. The sensifour-fifths rosin and one-fifth turpentine, the; concentration of rosin was..': ,calculatedj ,onf'th e, basis of 80% rosin content i'n' the gum In the above examples, in Tables I andII, that source material ranged from, crude! gum through WG rosin to FF Wood rosin. The rosinateproda uct in each of these cases wasqsnow white. That. from the FF wood rosinwasnnot 1S0; beautifully snow white as the others, yet:even. in this case f: the product, when dissolved in watenandprecipb' tated by addition of salt gavena-product which, in soap would have been satisfactory- 1 These examples illustrate the-merit of having, high concentration of rosin in the solvent, the limit being. reached. onlywhen the mixture "becomes toothick to-stir-or filteru First, the colored material. (the coloredrosinates as-well as the colored resenes) #is thereby-readily held in solution. Second, it is' possible to obtain good yield of ---high quality material in-a single'opera-- .40 tion without the necessity of=recyclin'g. "I 'hird, it ren'ders unnecessary many details of manipulation-which becomes advisable when the strength of certain ofthe-va-riableslies in-a more-critical zone, -as-indicated hereinafter. -'And-a-fourth advantage is that very cheap grades of rosin, such-as'FF-wood; canbeempl'oyed.

' If, as -in the above examples ot preferred -practice,--there'--=isso much rosindn the solvent that its weightappro'aches-or about equals theweight I of thesolvent, this may bis-considerednormal in thesense that the process will work comfortably even thoughthe quantity of alkali, thetemper'a' ture; or the grade -of-- rosin, or-'all of these,--lie in zones which under other conditions mightbe considered not so good. But if'the-ros'in is only abouthalf as much 'as' 'the solvent,-by weight, or less, the conditions' of alkali,-temperature and gradev require} critical consideration and restriction, lest "the s'odium rosinate obtainedfail of having the characteristic white, or'jnear 'white ness, of th invention, -or be notfree' from unsaponifiable matter. I

Practice of this invention in sucha" less concentrated-solution is what was'referred to herein before as having conditions inac'riticar Zone. Considerable variation of some of these conditions can still be allowed but such factorsas the quantity of alkali, thetemperature of filtration, and thegrade -of "rosin'niust be considered much more carefully than is the case withj the -very concentrated solutions. Observations follow as to adjustment of alkali, then of the temperature, and next of the grade'of resin to be selectedas a=sourcemateriali I I I If the processistob'e practiced-with needfor .tivity;.is callsedffbythmdanger that within the customary time periodzlso 'muchrosinfwill bearemovedNas-roS'ina-te, from; the solution that the desiredWretention of; the, dark colored, rosinate in solution may not be realized. Y

Elia some of the dark; sodium rosinate ceases. to be held inn-solution:theiteniperature of reaction maydoe raised, in order to::assure that thejdark rosfinate shall stay infgsoluti'on. Irrithese lcases'a drop-in temperaturezfito 1110f C. orwlowenbefore filtration' will cause g przeciiiitationcgof moss-like aggregates-bf dark sodium -rosinate and. .these contaminat the product so as to renderitunsuitab'lefonwhite soap. To increase the solubility-oi thedark' ro'sinate the temperature of filtration: must alsobe---raised; and the-filtration process itself mdsflbe-as rabid as possible "(-for example, a filtration by centrifuging in order'to complete the =separating beforethe'dark-rosinate will have begun to precipitate. Theymore'the alkali becomesconsumed, i.;e."the further the progress toward neutralization of all rosin acids present, within the time allotted for reactionfth'e greater-is the danger of precipitation pf 'dark rosinatef occurring andthe greater is the care requiredto avoifl thatduring'filtration. I

When operationsare within the-critical zone thelgrade of resin selected for the starting material -is--- of considerable importance. Light colored rosins Whi$h'-"COn taln a 'minimum' of colored material are muchbetter than the darker grades'of rosin. One of the;best grades for-production of white rosinate is crude gum; because of the) smallness of the proportion of colored acids present.

The tabular showings-of test examples which follow illustrate the varying' eflectsobtained with the difiering relations of materials, proporti n temperatures, kinds, etc, therein shown. I 'In IableflIIIf-the color ofthe-ro sin'ate obtained, ranging irom'snowwhite to tan,- in'all cases was betterth anthe sodium rosinateprepared -by gonventionalEn'iethods. The. temperature at which sodium" rosin'ate was recovredby filtration-was belowY-l lo" 'Cffort-he better grades of product. Where th e gyield was high, however, higher texnperatureswere employed. even up to in order 'toreduce precipitationof dark sodiuin fro which is aptjto' occurIat this co'ncentra on of resin in the 501mm; The temperatures; the, maximum, and were those reached abo w ll! e s) n. 1 1 out 11. 7 .car a e.wesi f t n ad .ia i. .n tllr eiqrtxem Agitation was continued I rosinates is less. In general, they show that the better results attend the greater; ratios of excess 1 rosin in solution, the lower ratios of carbonate 1 to rosin, the lower temperatures, and the shorter reaction times. However, in all cases, dark can be shownzby retrieving the remaining acids I I as the sodium salts and comparing their color colored sodium rosinates have been removed, as v of course readily separated from the rosinateby warming in a vacuum, or by otherwise allowing it to evaporate. a V i Mixtures of solvents can be used.-

Dried sodium rosinate may be added to a solution of rosin in petroleum as mentioned in-the first'illustration of the theory of the process. 1 Also partially neutralized rosinate can be used;

These and many other variations can be used withoutdeparting from the fundamental nature of the process, these being. merely adaptations such aspersons skilled in chemical processes 4 would apply at convenience.: L 1

The invention can be practiced alkali in with that of the material separated in the process. q e is if the PmPQ ti s rQSi ros- TABLE III I Y I WG rosin and NG2CO3 in kerosene I I 1..

' T 11 SW; Bitmls 01 Naoo $3, 9 alkali to Time, Yield, ght 1 tem rosinate 5 2 cc. in solution, 0 Percent color p r nt es I '00F1,150 as 11. 1 156 2.25 41 Suowwhlte; 85 1,150 34 11.1 159 2.25 41 Do. 18 1,150 22 25.6 112 .5 60 ,White. 1,150 3 22 182 2. I '59 Gray white. 80 1,150 22 2112 119 4.25 021 Do. Y 80 1,150 22 26.5 ,189 3 09 Do. 80 1,150 22 26.5 110 a 14 'Do.

54 1,150 15 1 21 185 2.25 1a Shady white. '00 1,150 22 a0 119 3.4 15 Do. 100 1,150 33.1 .184 a 19 Cream white. 100 1,150 22 33.3 182 2.25 82 Light tan." 1 0 1.150 28 0 192 3 s2 Tan.

In computing the concentrations of rosin'the specifi'c-gravity of kerosene; is taken as 0.73.

In Nos. Sand 9 lowratios of alkali to rosin are seen to go with snow white rosinate.

In Nos; 10-19 higher ratios of alkali to rosin, higher temperatures, and longer times of reaction,

' are seen to go with reducedperfection of whitee 1 ness, 1. e., lesscomplete separation of dark colored rosinate. 1

The practice of the invention seen in the forej I goingillustrations is capable of many modific'a 1 tions without departingfrom the essential prin- 3 ,ciple of retaining dark rosinates saturating a'solvent for rosinates so that white rosinates do not dissolve. Among such variations thatwi1l---be mentioned below are routine-modifications which may beintroduced during commercial adaptation, r

H Thepetroleum solution can be fortified withl fresh rosin, and re-used-a number of times, be-

jorethe dark material need be separated from it 1 i and the petroleum recovered by distillation. The

better thegrade of rosin employed, the more timesthepetroleum can vberecycled.

I ,When can; rosinate shows a tendency to come outduring the filtration, and the product is to be washed, the initial washings can be made with a i 'warmtoh'ot solutionof kerosene containing-a little, rosin; then with .warm petroleum nex't with: petroleum at room temperature; and then finally .with Zl owboiling petroleum. 111e, 11 1 1 solvent is inate, and solvent atthe end of the process are suchas to permit retention of the dark rosinate in solution. But aside from possibly; aiding rapidity of neutralization of the rosin acids,:and a more be distilled from the reaction'mixture with conexcessively large apparatus, distillation of much solvent, generally higher temperatures; additional expense, and also raises thedanger of having the water contributes little ot value, andthe intro-,1 duced water must later be removed.

As the quantity of water is increased the dim-'- cultyof its removal becomes-greater;More.s01

vent must be used, so that evaporation of the hydrocarbon solvent 5 will facilitate the removal of the water. The rosinate is very apt to form a gel, which makes stirring more and mor difiicult, and requires stillmore solvent to thin the mixture to asuitableconsistency. The temperature must be raised higher and higher, in order to drive out the water, with result that above C. the danger of cracking the rosin, or causing other undesirable changes, is increased. In the end th extra solvent must be distilled from the mixture, vuntil the rosin concentration is suitable for holdingthe dark rosinates in solutionwhile the-white rosinate material separates. The use of much water makes it necessary to recirculate or add petroleum until at theend of the process th operator maywell haveused four, five, or even as much as ten times the amount of solvent necessary, all of which must sequent danger of injuring the product.

, -The method above described for arrivingatthe preferred state employs anhydrous materials and adds more alkali than is necessary to neutralize the rosin, sometimes an excess of 50% or more, but this practice seems as good a if not better than 'one which, by' introducing water, requires reaction mixture set .to-a= gel or if injuring the product by employing high. temperature, any of which'might nullify the commercial value., -;Ex-

.cess of dry alkali,: a nd vigorousastirring, are used snowwhite product obtained;the yield being tinguishing visual characteristic that-the solid is Woodrosin, particularly the FF grade, is generally considered to be all-inferior variety, by reason 'of the large number and variety of color bodies present. Illustrations have been given in Tablelof'the use of these materials in hig h 'per cent rosin solution. -Tab1e VII shows the application me .zone of more critical concentration. In'all cases. colored rosinates areremoved,.but the degree of whiteness is not as high as that given in vTable I. In thecase ofFF wood rosin, after the rosin 'wasdissolved in the kerosene, the

solution was preliminarily filtered to remove the considerable quantity of matter insoluble inethe kerosene, and than was treated asdescribed. Successful results from very poor grades of rosin are partlyaffected by -theinsolubility of its extraneous matter in the solvent. As theponcentration of rosin in thekerosene solution diminishes, more of this insoluble matter is found pre V salts'of other fatty acids in the manufacture of I 57% V 7 white.

A 'TABLE'VI 'Pale'crude'gum, which would produce 'WG'ifOSiYl, and NazCOa in kerosene R b 'r tl ti t i" M s di Y Na alkali to Time Yield i No. calculation, 1n1x -bywelghtln1 temp. rosinate V I g. a sixgfif, o0 chrsn. percent I" V 470' 85 1,750 as 'l8. 7' 149 2.2 57 Snowwhite. 2s-.---- 473 1a 1,750 as 21.9 190 3.0 70 White. 1 27 474 120 1,750 as 20. r 188 2.3 ,66 Do.

I I-Iaving the detergent properties that characterize all rosinates it can be mixed with the soap, and its standing as a rosinate which has properties, distinctive from those of other rosinates as above indicated constitutes the product an improvement in rosin soaps in which the rosin present cooperates benignly with the other ingredients, without the depreciating efiect heretofore experienced. I I I V Y In the appended claims, the'terminert, ap-

plied to the liquid solvent,- indicates only its la'ck of reactivity with the substancesthat may be present, 1. e. alkali, water, unneutralized rosin acids, rosinates, resenes, esters and whatever other products remain after rosin-has been treated with-a-base; rosin, unless'contextindicates otherwise, signifies a body whose acid component is unneutralizedrosin acids; ,concen- 'cipitated with the precipitation" of rosinate.-

tration of rosin rin the solutionmwnsthe at 'QTABLEVIIQ i2; Wood rosin=a1td NazC-Os. in kerosene I :2 i"t.1 "Joncentra-J f M r di a g r 7 mp0,, H- W alkali to Time, Yield, 2 'No.' f V- 115353 J m W56?" 'hrs.. percent mgg gs e percent percen I a I e 28.; Ft weed 400.- e 750 28 12.5 160 2.5 v 22 only white. I 29;. FFwood 303-- s5-*1,75o 122 i 21.1 160 2.5 4e Lightbrowrn so Kwood 537--- so 71,750 e 37; 14.9 142 1.5 34 Snow white.

Y Abietic acid is the product of isomerization of therosin acids under'acid influence. The commercial product containSthe dark rosin acids i which make this material degrading when used infso'aplj Practice of the'present invention on this productled to isolation of a white sodium abietate: Commercial abietic acid, g., was. dissolved in enough kerosene to make a volume of 285 cc. The mixture was then he'ated'to" Cvat which temperature 36 g. of anhydrous s05 dium carbonate was added. The mixture was mechanically stirred, as in the other cases, was

heated to 149 C. during the course of an hour,

and-was maintained at between 149 C. and-152 C. forone hour longer.

tatewas recovered. V

These numerous illustrations show the wide By. the 'usual cooling, filtration and washing, snow white sodium abiee materialswhich' can be employed; Fromany of 1' such the process of the invention-can produce f a rosinate that is white, isolated from all dark rosinates as well as from'all resenesesters'and all other dark'or unsaponifiable substances. -The white rosinate thus isolated can be described asthe' sodium orlpotassium salts of rosin acids'which, when insolid "state, have the disof rosin to the total of resin itssolvent by weight; rosinate refers to the, heterogeneous mixture of rosinates producedby neutralization of the various .acids that may be present in rosin,

and includes the rosinate of'any one 'of ithos'e acids in a pure form'of the acid; e. g. ab'ietic .acid; and white rosinate is considered tobe isolated? when it is separated from other rosinates, and substances contained in or derived from rosin, as rosin is known incommerce; re-:

gardless that non-resinous substances, e. g. alkali or petroleum, may. be mixed with it or'adhering to it.

"Iclaim as myinvention: j 1. A process for dividing white alkali metal rosinate from dark alkali metal rosinate characterized by the step "of subjecting a hetero geneous mixture of alkali metal rosinates to the solvent action'of a solution of rosinin kerosene, in whi'ch'the rosin-kerosene solution holds in;

solution all dark rosinate ofthe mixturabyitsaflinity'for dark rosinate in preference to "white rosinate; white rosinate that was in the said mix 7 ture and not taken into the rosin-kerosene so1ution being left in solid form. 7 e 2. The art of separating white alkali metal rosinate from other alkali metal rosinates, char I V acterized by the step that'all of the saidrosinate's I which is present.

3. A process for dividing white alkali metal rosinate from dark alkali metal rosinate characterized by the step of subjecting a, heterogeneous mixture of alkali metal rosinates to the solvent I action of a solution of rosin in a petroleum solvent, in which the rosin-petroleum solution holds y in solution all dark rosinate of the mixture, its affinity for dark rosinate in preference to white rosinate, while some white rosinate of the said mixture remains undissolved.

4. A process for dividing white alkali metal rosinate from dark alkali metal rosinate characterized by the step of subjecting a heterogeneous mixture of alkali metal rosinates to the solvent action of arsolution of rosin in a liquid organic solvent, which said organic solvent by itself alone is not a solvent for rosinate, is chemically inert to rosin, to rosinate, and to water, and is immis+ cible with water, in which step the rosin-organic solvent solution holds in solution all dark rosinate of the mixture, by its aifinity for dark rosinate in preference to white rosinate; and some white rosinate of the mixture stands undissolved.

5. A process for segregating alkali metal white rosinate from other rosinates in a mixture of rosinates by holding the mixture immersed in a solution of rosin in a liquid organic solvent, which said organic solvent by itself alone is not a solvent for rosinate and is chemically inert to rosin and to rosinate and to water and is immiscible with water, in which said solution a concentration of rosin is maintained such that the rosin-organic solvent solution has a dissolving capacity for rosinates, determined by the quantity of rosin present, which capacity is commensurate with a dissolving of all dark rosinate thatv is present but not all white rosinate that is present, by preferential aflinity of the rosin-organic solvent solution to dissolve dark rosinate before it dissolves white rosinate; followed by filtering out the undissolved matter.

6. A process for producing alkali metal white rosinate apart from other rosinates; following a reaction in which a salt of an alkali metal is reacted with rosin that is in solution in a liquid organic solvent, which said organic solvent by itself alone is not a solvent for rosinate and is chemically inert to rosin and to rosinate and to water and is immiscible with water, thereby producing heterogeneous rosinates, in which process, after the said reaction, the concentration of rosin and the saturation point of the rosin-organic solvent solution for'dissolving rosinates, determined by that concentration of rosin, are made commensurate with a dissolving of all dark but not all white rosinate that is present, determinable by sampling and testing, by preferential afiinity of the rosin-organic solvent solution to dissolve dark rosinate before it dissolves white rosinate.

7. A process for producing alkali metal white rosinate apart from other rosinates, as in claim 6, characterized in that during the said reaction and process the concentration of rosin varies from an initial high proportion, approximating equality with the weight of the organic solvent, down to a final lower proportion sufficient to holddissolved all dark rosinate that is present after the reaction but not sufficient to dissolve all white rosinate then present; fluidity of the mix during reaction being maintained by heating and stirring.

8. A process for producing alkali metal white rosinate apart from other rosinates as in claim 6, in which, during the reaction, the liquid body in which the reaction is occurring is maintained free from water.

AVERY A. MORTON. 

